In the mining of coal, or like material which must be mined in high volume, it is very desirable to expose the operators to as few safety risks as possible. This is conventionally done by utilizing mining machines which bore into an area to be mined and continuously remove the cut coal from the mined area. In order to make such mining machines most economical, it is desirable to cut coal during retreat from the mined area, as well as during advance into the mined area. This has been successfully accomplished by mining machines such as shown in U.S. Pat. No. 4,082,362. However even though such machines are successful in cutting both during advance and retreat, cutting during retreat is much slower than desirable since the conveying action during out cutting is not as efficient as the conveying action during in cutting.
According to the present invention, a mining machine and method of mining coal or the like are provided which have efficient conveying mechanisms such that it is possible to effect out cutting substantially as fast as in cutting. This is accomplished by providing conveying means that act in such a manner that the mining machine is essentially "advancing" both during in cutting and out cutting.
According to one aspect of the present invention, a mining machine for out cutting substantially as quickly as it in cuts is provided.
The mining machine comprises a frame, a front cutting means mounted adjacent the front of the frame, and a first conveying means for conveying cut material from a front portion of the frame to the rear, and ultimately out of the area being mined. A second conveying means is mounted in back of the front cutting means, for conveying cut material from adjacent the rear of the frame toward the front, to be deposited on the first conveying means. A rear cutting means is located to the rear of the second conveying means for cutting material to be moved to the second conveying means as the machine is moving rearwardly (i.e. during out cutting).
According to a first preferred embodiment of the present invention, a mining machine is provided which comprises the following elements: A frame. A front cutting means mounted adjacent the front of the frame. A chain conveyor extending rearwardly from adjacent the front cutting means to convey cut material to the rear and ultimately out of the area being mined. Shroud means pivotally mounted adjacent the front end thereof mounted on the frame along the length of the first conveying means. Conveying means mounted adjacent the front end of the shroud means and above the chain conveying means for conveying cut material from the shroud means to the chain conveying means. And, rear cutting means mounted to the rear of the shroud means, and mounted for movement from a first, inoperative position within the volume defined by the front cutting means, to a second, operative position, outside the volume mined by the front cutting means.
According to a second preferred embodiment of the present invention, a mining machine is provided which comprises the following elements: A frame. A front cutting means mounted adjacent the front of the frame. A chain conveyor extending rearwardly from adjacent the front cutting means to convey cut material to the rear and ultimately out of the area being mined. A pair of universal conveyor chains, are mounted on either side of the conveying chain, and disposed within a channel having an inwardly arcuately shaped and positioned portion to deposit cut material onto the conveyor chain. And, rear cutting means located to the rear of the universal conveyor chain, and mounted for movement from a first, inoperative position within the volume defined by the front cutting means, to a second, operative position, outside the volume mined by the front cutting means.
According to the present invention there also is provided a method of mining material, such as coal. The method comprises the following steps: (a) Cutting into the area to be mined using a mining machine by moving the mining machine in a forward direction, to form a bore having given first dimensions. (b) Removing cut material as the mining machine is moved in the forward direction by moving the material rearwardly out of the area being mined. (c) Terminating forward movement into the area being mined, and then moving the mining machine rearwardly out of the bore while continuing to cut material so as to enlarge the bore from the first dimensions to second dimensions greater than the first dimensions. And, (d) conveying the material cut during rearward movement first in a forward direction, and then ultimately rearwardly so that it moves out of the area being mined in the same manner that the material cut during forward movement is moved out of the area being mined.
It is the primary object of the present invention to provide the rapid out cutting of coal or the like during mining with a mining machine. This and other objects of the invention will become clear from an inspection of the detailed description of the invention and from the appended claims.